Final answer:
DDT was introduced in World War II as a potent pesticide, leading to its widespread use until the 1970s. Environmental concerns, bioaccumulation, and the emergence of pesticide-resistant pests led to its ban in the U.S. Despite this, DDT's effectiveness in controlling malaria makes its usage a continued subject of debate.
Step-by-step explanation:
The history of DDT usage dates back to World War II, when it was used to control malaria and typhus among troops and civilians. Its effectiveness in controlling pests on a massive scale led to widespread agricultural and domestic use. However, DDT's persistence in the environment and its accumulation in the food chain caused significant harm to wildlife, particularly birds like eagles, whose eggshells became thin and fragile, leading to decreased populations.
In response to the growing environmental concerns, highlighted by Rachel Carson's book 'Silent Spring', the US government banned DDT for agricultural use in 1972. Other countries eventually followed, although the issue of DDT use remains contentious. This is due to DDT's effectiveness in controlling deadly diseases like malaria, which resurged in places like Sri Lanka after DDT was abandoned. The development of resistance by pests and the incidental contamination of food with DDT also contributed to its decline in usage. Despite its ban, DDT is still considered a critical component in the fight against malaria in certain parts of the world, causing ongoing debate about its risks versus its benefits.